Danielle DeInnocentes waited in line with her father for nearly 14 hours to welcome California-based In-N-Out Burger to Texas. Her first bites of a double-double brought tears to her eyes.

“Wow, I’ve missed you,” she told her burger.

DeInnocentes was among the hundreds who thronged to the fast-food chain’s openings Wednesday in Frisco and Allen to order off a menu that hasn’t changed since 1948.

California transplants Ron Russek II of Cleburne and newfound friend Kip Cummings of Lufkin had been camped out since Monday night so they could be the first in line at the Allen restaurant. Russek’s first bite on Wednesday? “Phenomenal.”

In-N-Out aficionados pride themselves on knowing the secret menu — burgers stacked “3x3” or “4x4” with that many patties and slices of cheese. There’s also grilled cheese (no meat), protein style (wrapped in lettuce, no bun), and animal style — a mustard-cooked patty with grilled onions, extra spread and pickles.

Pedro Gonzalez, a California native who lives in Arlington, had to start his In-N-Out vigil at 9 p.m. Monday to be Frisco’s first customer. He couldn’t wait to eat his favorite: a 3x3, animal style. “It’s like a long-lost relative that I’m getting reacquainted with.”

Many of the diehards in line Wednesday hail from California. Experts say there’s a reason.

“There’s nothing like food from home, whatever and wherever that happens to be,” said Martin Deschner, a clinical psychologist and associate professor at the UT Southwestern Medical Center. The strong response, he said, comes because “it is seen as familiar and safe, like an old friend.”

Doug McIntyre, who has studied companies’ loyal followers as founder and CEO of Ohio-based Cult Marketing, said, “It is very much about emotion. It’s not rational.”

A company’s exclusivity and special lingo also can play into its cult status, he said.

Steven Arxer, an assistant professor of sociology at the Dallas campus of the University of North Texas, said he planned to take photos of Wednesday’s crowds to use in his collective behavior class.

“You see this all the time in Apple products,” Arxer said. “People abandon their homes, everything they’re doing, for a product.”

Hype from the media and social networking sites further legitimizes the behavior, he said.

Such rabid receptions aren’t new to North Texas.

In 1999, North Carolina-based Krispy Kreme sold 800 dozen doughnuts in its first two hours in Arlington. Steak ’n Shake’s 2002 opening in Grapevine prompted one customer to drive from Arlington almost every night for two months for its “steakburgers.”

And an estimated 25,000 people showed up to shop at Swedish furniture maker Ikea on its first day in Frisco in 2005.

Next on the list: California grocer Trader Joe’s.

‘It took me back’

DeInnocentes said her In-N-Out visit Wednesday flowed with nostalgia. “It took me back to Fontana and San Bernadino and to living in California,” she said.

Al Miramontes, 51, and son Matt Miramontes, 23, of Allen said they’ve gotten by on Whataburger and Steak ’n Shake since moving from California six years ago. But those places just weren’t the same as In-N-Out.

“Now we don’t have to argue about where we want to eat anymore,” Matt Miramontes said.

Jessica Lozano of Fort Worth stood in line for several hours. After eating her burger, the 35-year-old hopped into the drive-through lane to take lunch to her co-workers.

“I used to take trips to California for In-N-Out,” she said. “This makes me feel like I’m in California.”

Workers cheered

As the line streamed slowly into the Allen restaurant, In-N-Out employees smiled and punched orders for double-double burgers and fries into the registers.

A faint beeping sound let the staff know when patties were ready. Sporadic thumps rang out every time an employee ran a fresh potato through a machine that cuts them into strips to be fried.

In Frisco, In-N-Out’s vice president of planning and development, Carl Van Fleet, said he’s been to plenty of store openings. But none have been like the North Texas opening. None has created the draw that North Texas did on Wednesday.

The family-owned company is known for its fresh ingredients — no freezers or microwaves allowed. Branching into Texas became possible only after In-N-Out opened a distribution plant in Dallas to create its meat patties.

“I’m going to gain a lot of weight. That’s all there is to it,” he said.

Hamburger memories

In-N-Out veterans can recall their last visits with ease.

“Last May in Vegas,” said Mike Stevens of Frisco, who had settled in for at least an hourlong wait in the drive-through lane.

The chain’s fare was Brian Smith’s mainstay for nine of the 10 days he spent in California in December. “Some days it was lunch and dinner,” he said.

Amber Richardson of Fort Worth brought a photo from her last visit to In-N-Out in Arizona. She wore a company shirt, boasted a sticker on her car bumper and even admitted to emailing company execs on more than one occasion to come to Texas.